1. Field of the Invention
The present invention relates to skin cleansing and exfoliant compositions and methods of treating skin.
2. Discussion of the Prior Art
The skin of the human body and, more specifically, facial skin, as well as the skin of certain non-human animals, periodically needs a deep cleansing to remove not only the oily particles resulting from secretions, but also dead skin caused by desquamation of the epidermis.
An exfoliant cleansing or "peeling" promotes the partial regeneration of epidermal tissues, restoring the skin's freshness and suppleness and favoring the application and the penetration of cosmetics or dermo-pharmaceutical products.
The cleansing of the skin can be achieved utilizing detergent solutions, but these have a tendency to cause pronounced drying of the skin without completely removing foreign matter.
There have also been proposed to effect the exfoliation of the epidermis compositions in the form of creams containing abrasive substances comprised of insoluble particles in the appropriate size and shape such as, for example, quartz particles which, after application to the parts of the body to be cleansed, are removed by wiping or rinsing with water. Such compositions are particularly effective but may be highly irritating. In addition, particles of the abrasive materials can remain in the pores of the skin and thus cannot be totally removed.
More recently, aqueous compositions in the form of creams which contain abrasives in the form of mineral substances or sugars with low hydrosolubility in the cream, but which can dissolve during the cleansing of the skin with water, have been proposed. Since the purpose of these compositions is to eliminate oily substances, these products are generally devoid of such products, but when they do contain them, they are present in a proportion less than about 5% by weight.
Since the abrasive particles have low hydrosolubility, their removal during rinsing with water is often slow and incomplete.
Moreover, by drying on the skin, the compositions present the inconvenience of not allowing a prolonged massage which is necessary to obtain proper exfoliant action.
It has been suggested to use cleansing compositions which leave the skin fresh and clean, totally free from oils, dirt and dead skin, by applying an anhydrous composition to the skin and massaging; this composition containing, in an oily phase, an emulsifying agent and highly hydrosoluble abrasive agents.
With one of the purposes of the cleansing composition being the removal of oil substances on the skin, the media for the compositions proposed to date do not contain fat bodies, or have only a relatively low concentration thereof, to avoid any addition of oils to the skin.
A number of products are commercially available which are directed to moisturizing the skin, thereby helping to maintain its youthful appearance and soft texture. While these products achieve varying degrees of success as moisturizing agents, research continues in an effort to develop more effective moisturizing agents.
Cells of the skin are constantly being generated during the natural cell renewal cycle of the skin. This cell renewal cycle involves the generation of new cells which rise through the epidermal layers of the skin until they reach the outer epidermal layer, or stratum corneum, where the skin cells die and eventually fall or slough off. Young skin renews its surface layers every two to three weeks, whereas mature skin may take twice as long to be renewed as compared to young skin. The longer the cell renewal process, the greater the loss of natural moisture on the skin's surface, thereby making the skin feel dry.
By accelerating the renewal of cells on the skin, the skin can be made to appear younger and fresher-looking. Many moisturizers currently available cause such acceleration by irritating the skin's surface to such a degree so as to cause sloughing off of stratum corneum cells. However, such irritation is not desired because of the potential damage to the skin.
The key to a more moisturized and, consequently, more youthful-looking skin is the proper conditioning of the skin. The proper "conditioning" of the skin requires, inter alia, the removal of dead skin cells from the surface of the skin.
It is known that cell renewal, i.e., eliminating old skin cells, encourages new skin cells. The epidermal cells are in a continuous state of regeneration and renewal. It has also been reported that the first signs of aging start to appear when a person is in his or her late 20's and early 30's. New epidermal cells are formed in the basal layer, the bottom layer of the epidermis. When they are first formed, they are round and "plump" (full of moisture). These cells travel through the four epidermal layers until they reach the surface or top layer, the stratum corneum. As they travel, they become older, flatter and drier-looking. By the time they reach the stratum corneum, the layer of skin that is seen, they are very flat and are ready to be shed or scraped off. As a person ages, cell turnover time, the transit time for which it takes new cells that are formed in the bottom or basal layer of the epidermis to travel through the various layers until they reach the top layer or stratum corneum becomes slower. It is documented that when a person is approximately twenty years old, the cells in the top layer of the epidermis will be sloughed off and replaced every two or three weeks. When that person is approximately eighty years old, the replacement can take up to twice as long. Since the epidermis is in a continuous state of self-replacement or turnover, with new cells being born in the basal layer to replace the old cells being shed from the stratum corneum, it follows that if the rate of cells in the stratum corneum that are being desquamated or shed is accelerated, the rate at which new cells are formed to replace them will also increase.
There are already available other procedures, both surgical and non-surgical means, by which cell renewal can be hastened to rejuvenate the skin so that the skin can retain moisture and have a more youthful, healthy, firmer and cleaner appearance. The reality is that none of these procedures are permanent. Because the cells are constantly being formed and surfacing to the stratum corneum, and must be shed at least every two or three weeks, the treatment, whatever the method, must be repeated. Moreover, none of the procedures are without some risk, either due to the techniques being employed or the varying expertise of physicians performing them. There is also the added risk and liability when the procedure requires the use of an anesthetic.
It is an object of the present invention to provide a novel skin exfoliant and cleansing composition and method which are not subject to the disadvantages noted above.